Air conditioning systems



y 1960 L. F. MEIRCATANTI 2,935,007

AIR CONDITIONING SYSTEMS Filed Sept. 9, 1957 2 Sheets-Sheet 1 FIG-5INVENTOR. I Lou/Ls I? Mertafanh y 1950 L. F. MERCATANTI 2,935,007

- AIR conmnoumc SYSTEMS Filed Sept. 9, 1957 2 Sheets-Sheet 2 y INVENTOR.I8, 24 [OH/3 finsmw' AER CONDITIONING SYSTEMS Louis F. Mercatanti,Trenton, N.J., assignor to Fedders- Quigan Corporation, Maspeth, N.Y.

Application September 9, 1957, Serial No. 682,887

1 Claim. (Cl. 98-39) This invention relates to air conditioning systems.

In air conditioning systems it is desirable to apportion a minor volumeof outside fresh air to the air that is being recirculated within theheated or cooled spaces of a building. This has long met with anobjection from a safety point of view, in that in the event of a firefresh outside air would be drawn into the building to feed the fire, atleast until such time as the motor driven blowers were renderedinoperative. It is proposed in the present invention to obviate thishazard by supplying a heat responsive mechanism, which will respond in apositive manner to close the dampers which permit fresh air entry.

The invention will be more clearly understood by referring to theaccompanying specification and drawings wherein:

Fig. 1 is a perspective view of an air conditioning unit with part ofthe casing removed to show the thermal damper control of the invention;

Fig. 2 is a verticalsection thru Fig. 1;

Fig. 3 is a section on the line 3--3 of Fig. 2;

Fig. 4 is an exploded perspective view of the thermal damper control.

For exemplary purposes the invention is shown organized with a heatingunit having a casing 11, wherein are housed motor driven blowers 12,which draw air thru a port 13 low in the casing and an overlying filter15 within the casing and then forcethe air thru a heating coil 14 andthence back into the room. The casing 11 is mounted adjacent a wall Wwhich is pierced to provide an inlet port 16 for outside air. The casing11 is provided with a registering port 16a, the opening of which iscontrolled by a damper 17 which is hinged, as indicated by the numeral18, to the base structure 19 of the casing 11. The damper 17 may becontrolled in any suitable manner; for example, by a manually operablebell crank 21 pivoted to the base structure l'l by a stud .22 andcarrying a spring wire 23 leading to andafiixed to' the damper 17; Abracket 24, adjacent the damper 17 serves as a mounting means fora guidesheath 25 for the wire 23 and also as a support for the mechanism of theinvention. 7

It will be observed that the mechanism 20 is not me.- chanicallyassociated with the operating members of the damper 17, being mounted asshown in Figs. 2 and 3 on the bracket 24 in spaced relation to suchmembersries a compression spring 30, which is retained by a nut 31 andwasher 32. The remaining end of the plunger 29 is formed with a hookterminal 33.

A stanchion in the form of a bolt 34 is secured to the bracket 24,adjacent to the bushing 27 by nuts 35, and the free end of the bolt isprovided with a hook terminal 36. A link or fusible element 37 ispierced with spaced holes 39 to receive the terminals 33 and 36 of theplunger 29 and bolt 34, respectively to complete the assembly. It willbe noted that the spring 30 may be suitably proportioned so that in thisassembly it will be placed under full compression with the nut 31 beinglocated immediately adjacent the inner face of the damper 17 and withthe link 37 retaining the assembly in such a preset position.

The link 37 is formed of a low-melting bismuth alloy,

which is fusible at temperatures around F. Thus, in the event of a firethe hot air drawn from the floor into the unit 10 first passes the link37, which in melting releases the spring pressed plunger 29 for a strongthrust on the damper 17 in the direction of closing of the damper, asshown in dot and dash lines of Fig. 2 Under normal conditions theelements of the mechanism 20 do not interfere with the opening orclosing of the damper or the operating mechanism for performing thisfunction.

It will be apparent that the mechanism 20 with slight modification maybe installed in many of the existing air conditioning systems adjacentthe outside air dampers thereof. It is, therefore, not intended to limitthe inventionto the precise installation herein described, except as maybe required by the scope of the following claim.

I claim:

In an air conditioning system including a casing having a fresh airinlet port, a damper within said casing, pivotal mounting means in saidcasing for mounting said damper for movement from a position coveringsaid port, manual operating means connected to said damper for movingsaid damper to an open position uncovering said port, a plunger, abracket mounted in the casing and including a bushing for receiving saidplunger for axial guided movement toward the body of said damper remotefrom said pivotal mounting means, a spring carried by said plunger andengaging said bracket, said spring being adapted to urge said plungerinto contact with said damper to retain said damper in closed position,said plunger extending thru said bushing and having a terminal remotefrom said damper formed with a hook portion, a stanchion carried in thecasing in spaced relation to said bracket, a fusible member havingspaced openings therein engaging over the stanchion and the hook portionof the plunger respectively, said fusible member retaining said plungerin a withdrawn position relative said damper to permit unobstructiveoperation thereof during normal conditions.

' References Cited in the file of this patent UNITED STATES PATENTS1,777,848 Harnett Oct. 7, 1930 1,816,217 Harnett July 28, 1931 1,966,956Dunn July 17, 1934' 1,981,200 Schultz Nov. 20, 1934 2,812,835 SmileyNov. 12, 1957

